The invention relates to a portable apparatus having data processing means and integrated screen means for displaying one or more graphical or other objects presented by said data processing means, said screen means having gravitation-controlled sensor means feeding said data processing means for measuring a spatial orientation of said screen means. It has been known to sense the spatial orientation of a display apparatus, for example a television monitor, and control the orientation of the image in such a way that the image is always oriented vertically and with the right side up. The inventor has found that various spatial orientations of an apparatus according to the preamble may control associated object motions on the screen, and has envisaged various useful applications of a device that is enhanced in such manner.